In switchgear and switchboard systems, run-over buses, such as A, B, and C phase run-over buses can connect between circuit breakers and terminal blocks. For example, in one implementation, run-over buses can connect between a load side of a circuit breaker and terminal blocks configured to attach to load cables. Running near these run-over buses can be various buses (e.g. horizontal buses) that carry A, B, and C phase line current to the line side of the circuit breakers. The horizontal buses can be interconnected to three-phase line power, for example. Within such switchgear there may be multiple circuit breakers, each having A, B, and C phase run-over buses connected thereto.
In such switchgear, it is desired to move the components as close together as possible to minimize overall space envelope. Such close proximity of various buses, such as run-over buses and thru (horizontal) buses under normal operating conditions is not problematic. However, such close proximity during a short-circuit event can cause substantial forces and bending of various components and if such bending is sufficiently large, it could be possible to have phase-to-phase short circuits or undesirable arcing. Forces encountered during such short-circuit events are approximately inversely proportional to the spacing between the various bus bars.
Thus, there is a need to improve various bus assemblies to improve strength thereof and allow such close proximity positioning of the bus bars therein.